Fludarabine, cyclophosphamide and rituximab plus granulocyte macrophage colony-stimulating factor as frontline...

Fludarabine, cyclophosphamide and rituximab (FCR), the standard of care for the frontline treatment of patients with chronic lymphocytic leukemia (CLL), is associated with a high rate of neutropenia and infectious complications. Granulocyte macrophage colony-stimulating factor (GM-CSF) reduces myelosuppression and can potentiate rituximab activity. We conducted a clinical trial combining GM-CSF with FCR for frontline treatment of 60 patients with CLL. Eighty-six percent completed all six courses and 18% discontinued GM-CSF for toxicity: grade 3-4 neutropenia was observed in 30% of cycles, and severe infections in 16% of cases. The overall response rate was 100%. Both median event-free survival (EFS) and overall survival (OS) have not been reached. Longer EFS was associated with favorable cytogenetics. GM-CSF led to a lower frequency of infectious complications than in the historical FCR group, albeit similar EFS and OS.